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<head>
    <meta charset="UTF-8">
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    <title>Document</title>
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<body>
    <script>
        let arr=[12,57,32,22,17];

        function sum(a,b,c,d,e) {
            return a+b+c+d+e;
        }

        //...arr等同于12,57,32,22,17
        alert(sum(...arr));
    </script>
</body>
</html>